I have size 40 pilot jets in my carbs with stock setup with F1S slip on. Many people have installed the 40 pilots and had great success with easier cold starts and quicker warm up times. Would the idle mix screws have any effect on startup?
Choke mechanism seems to work OK. I am putting on UNI pod filters (from last years race bike) and am bumping the mains to 140. I'm also replacing the pilot jets cuz they're cheep and I wasn't sure if I had the 40's or not. Have to change them now cuz I tore the old ones up getting them out.
The goal is to ease cold starts, improve idle, and get this thing to run better.
But is it actually starting? Or does it take a long time to warm up so it will run smooth off the choke? Details man!
It eventually starts. Just takes a lot of cranking and cranking and cranking and cranking when it's cold...sub 55 deg F.
When it is warm...above 70 deg F, it seems to start fine.
I think I f'ed up my starting motor with all the damn cranking. :o
When it does start, it takes about 2 miles at 55-70 mph to get warm enuf to take off choke.
Air screws...start at 3...but if the motor has more blow by you will probably need to open up more. Also check your float level. They should be right at the gasket level and no more.
Cool.
Srinath.
What he said.
When you put the bigger pilot jets in richened the idle circuit way up. You have to adjust the pilot mix scews acordingly...
Cool.
I put in new pilots and the 140 mains and set the mix screws to three turns out. As soon as I get the shim I need, I'll have her back together.
Thanks guys.
With Uni Pods you may want to try 145 mains or so. Never tried it myself but I think 145 is about where it might be. Some one here tried to jet with those...Shall we call it stage 2...So where did they end up...
Cool.
Srinath.
Quote from: seshadri_srinathWith Uni Pods you may want to try 145 mains or so. Never tried it myself but I think 145 is about where it might be. Some one here tried to jet with those...Shall we call it stage 2...So where did they end up...
Cool.
Srinath.
Dude, I researched a bunch of posts about different setups and jetting suggestions. Believe it or not, you recommended starting with 140's with UNI pods and stock pipe. Remember, the F1S is about sound, weight, and looks. No real flow advantage. Anyway, I'll start with the 140's and it won't be difficult to install different mains if it needs it, especially with the airbox gone.
I HATE that f'in air box.
Grrrr.....
Yea yea Hide behind what I said...Well its just a guess in any case...I have never done it...and those that have didn't post back so we are screwed...so when you get it right post back here.
Cool.
Srinath.
Quote from: seshadri_srinathWell its just a guess in any case.
Yeah, I know. ;)
I'm going to pick up a pair of 145's to have handy, too. :thumb:
Its not always a guess...All the stuff I have done (6 bikes personally and 2 bike by reliable friends) I am sure of...Just the setup you have I never tried it myself. Post back here and we can add it to the overall jetting knowledge pool.
Cool.
Srinath.
I have uni's (oiled of course) w/ sv650 pipe, 40 pilots, 140mains, needles shimmed w/ 1 spacer, and one slider hole plugged up. Runs wonderfully... @ summer day temp... Cool nights seems to put a hamper on the fun a bit. Or maybe that's just the "survival reaction" against pitch black roads kicking in.
I was thinking about popping in 145's that I have, but it "ain't broke" right now, so I'll wait till I need to re-oil the filters again to try it. BTW, I bought mikuni jets with "RD" engraved in, these don't seem to be factory mikuni jets as they are cut differently... I don't know if this changes the jets sizes I mentioned.
SS
If your problem is up in the top 1/2 of the revs/throttle opening then yes bigger mains will be the ticket. You have stock needles right...shimmed 1/2mm??
Thanks.
Srinath.
I shimmed the needles with two washers each. Should I try one washer first b4 putting the second ones in?
2 shims for a 1 mm total right...I have 2 shims in mine too...its likely to be right or close. The overall needle is heavily dependant on the mains. Settle on the mains first and then try 0-1-2-3 etc...
Cool.
Srinath.
Hey, take it easy Srinath! I'm the guy who never posted his Uni Pod results... and with good cause. Just got the bike up and running yesterday (had some problems with the cross-drilled 40 pilots :x ). Actually, you suggested that I start with 135 mains and work my way up. Trouble is, the K&N kit only came with 132.5s, and I've got those in it right now. Runs fine in the lower revs, but up top its a dog. At about 70 it starts dying out on me. I hit 95 last night and I thought it was going to conk out on me right in the middle of the highway.
So I agree... bigger is better with the Unis. I'll try 145s next to see what happens. And this time I'll post :)
BTW- Thanks for all the help.
Emmett Lyman
K&N doesnt go by the Mikuni jet sizes so 145 wont be right with your K&N kit.
Do you happen to know what a K&N 132.5 is in Mikuni speak?
Thanks,
Emmett Lyman
K&N is the same as mikuni...140 in mikuni is 1.4mm dia, and so is K&N...K&N needles are entirely different though. That is where all their tech is. Now I asked you to try 135's but was that with K&N needles or stock.
Anyway most of my jetting is bsed on stock needles.
Cool.
Srinath.
Ahh... that might explain why the bike is, all things considered, not running that badly. I'll give the 135s a shot (with K&N needles) instead. The bike is already running better than it ever has before... I can't wait to get it tip top!
Thanks,
Emmett Lyman
Try just swapping to K&N needles instead of the stock. You have the stock needles right. Just put in K&N ones and try it. That should be near perfect.
Cool.
Srinath.
OK, here's the deal. I've got the K&N needles in along with the K&N plugs... all per the instructions that came with the jet kit. I've also got 40 pilots, 135 mains, and the mixture screw 3.5 turns out. This setup is coupled with the Uni pod filters and a stock pipe. The bike runs incredibly well now... much better than it ever has before. Starts right up, and pulls strong the whole way through the curve. The only ill performance I'm still getting is up at 90+ in 6th (This is ~8000 rpms: I've also advanced the ignition ~5 degrees). There's still some hesitation at that speed, so I'm going to try out some 137.5 mains. If those don't help, then I'm pretty sure I'm just maxing the engine's power output. If they solve the problem, well, better still!
Thanks all, I've never had it so good! :thumb:
Emmett Lyman
OK Plugs mean those white things to block off one of the slide holes right. OK K&N supplies a 134 as their largest jet. 8K should be fine on this bike, even one as worn out as my 89 dont run out of steam till 9K. Better motors should make 10K easy in 6th. So 137.5 may help, but K&N recomends lifting the needle some more if it doens't behave at 134 mains. You are real close but I think following K&N's advise may be easier and work out just fine. Their needle profile is very steep in the lower 1/4 inch so they may have this situation addressed in the design of it.
Cool.
Srinath.
Ahh... good idea. I'll try the washer instead. Either way, I'm pleased with the way it's running :).
Emmett Lyman
With K&N you need to slide the clip down into a lower (as it sits in the carbs on the bike) groove. Washer technique is just a more crude way of accomplishing this on the stock needle.
Cool.
Srinath.
Even better! I guess there are subtle benefits to the jet kit after all (still not worth $30, though). If I'd trusted my instincts, I'd have followed your do-it-yourself advice from the get go. I'll know better next time!
Thanks,
Emmett Lyman